US Democratic presidential front-runner John Kerry has won the backing of former rival Richard Gephardt.
Mr Gephardt, a Missouri congressman who dropped out of the race last month after a disappointing finish behind Mr Kerry in Iowa, will endorse him at a campaign event in Warren, Michigan, on Friday. The two will appear together at later events in Michigan, which holds its nominating contest tomorrow.
Mr Gephardt's backing for Mr Kerry is expected to lead to an endorsement of Mr Kerry by a coalition of labour unions that had backed Mr Gephardt, with an announcement likely within the next week after union leaders conferred with members, labour sources said.
With five Democratic nominating contests scheduled over the next five days, Mr Kerry's challengers are frantically raising money in the hope of derailing the Massachusetts senator before he runs away with the nomination to face President George W. Bush in November.
At separate appearances in Tennessee, Mr Wesley Clark attacked Kerry's "hypocrisy" and Mr John Edwards tried to draw distinctions between their trade policies as the White House hopefuls chased Mr Kerry across five states.
One-time front-runner Mr Howard Dean looked beyond the next five contests and drew the line at the February 17th primary in Wisconsin, telling supporters in an online fund-raising appeal that his fading campaign must win there or he would be finished.
"The entire race has come down to this: We must win Wisconsin," said the former Vermont governor, who has squandered a huge lead in the polls and a $40 million bank account.